System and method for actuating tools downhole

ABSTRACT

A technique facilitates actuation of a downhole tool in a well string. The downhole tool may be actuated hydraulically via the controlled flow of a hydraulic fluid under pressure to the downhole tool through a port. Flow of the pressurized fluid through the port is controlled by a barrier member which may be opened by a plunger working in cooperation with the barrier member. Movement of the plunger is controlled by selectively increasing the pressure acting on the plunger through, for example, actuation of an expansion device or other suitable device.

BACKGROUND

In a variety of well related applications, downhole tools are actuatedto perform desired functions. For example, packers, valves, and otherdownhole tools may be selectively actuated at specific times during adownhole procedure and/or at specific locations within a wellbore.Several types of mechanisms have been employed to enable actuation ofthe tool at the desired time and/or location.

For example, rupture discs and other shear mechanisms have been employedto control actuation of one or more downhole tools. However, suchmechanisms often limit the number of tools that can be operated in apredetermined sequence. Additionally, these types of mechanisms can bedifficult to use in applications and environments in which the maximumpressures available are limited. Intelligent triggering devices alsohave been used to control the selective actuation of downhole toolsbased on signals delivered to the intelligent triggering devices. Invarious environments and applications, however, some of these types ofdevices can be difficult to use or unreliable. Explosive materials alsohave been employed to open flow paths downhole. However, components withexplosive materials can be difficult to ship or transport to a well sitedue, at least in part, to governmental regulations on handling andtransporting such materials.

SUMMARY

Embodiments of the claimed system or methodology may comprise the use ofa downhole tool in a well string. The downhole tool may be actuated viathe controlled flow of a fluid, e.g. a hydraulic fluid, under pressureto the downhole tool through a port. Flow of the pressurized fluidthrough the port is controlled by a barrier member which may be openedby a plunger working in cooperation with the barrier member. Movement ofthe plunger is controlled by selectively increasing the pressure actingon the plunger through, for example, actuation of a gas generatingdevice or other suitable device.

BRIEF DESCRIPTION OF THE DRAWINGS

Certain embodiments of the disclosure will hereafter be described withreference to the accompanying drawings, wherein like reference numeralsdenote like elements. It should be understood, however, that theaccompanying drawings only illustrate various implementations describedherein and are not meant to limit the scope of various technologiesdescribed herein. The drawings are as follows:

FIG. 1 is a schematic illustration of a well system deployed in awellbore in which the well system comprises a downhole tool that may beselectively actuated by a tool actuation system, according to anembodiment of the disclosure;

FIG. 2 is a schematic illustration of an embodiment of the toolactuation system illustrated in FIG. 1, according to an embodiment ofthe disclosure;

FIG. 3 is a schematic illustration of another embodiment of the toolactuation system coupled to a downhole tool, according to an embodimentof the disclosure; and

FIG. 4 is a schematic illustration of another embodiment of the toolactuation system, according to an embodiment of the disclosure.

DETAILED DESCRIPTION

In the following description, numerous details are set forth to providean understanding of some illustrative embodiments of the presentinvention. However, it will be understood by those skilled in the artthat various embodiments of the present invention may be practicedwithout these details and that numerous variations or modifications fromthe described embodiments may be possible.

As described herein, a tool actuation system may be utilized with avariety of downhole tools to provide dependable actuation of one or moredownhole tools in a variety of well related applications. By way ofexample, the tool actuation system may be used in cooperation withdifferent types of downhole valves, packers, and other downhole toolswhich are actuated by a fluid, e.g. a hydraulic fluid, under pressure.In many applications, such downhole tools may be actuated by thepressure of well fluid. The tool actuation system is designed toselectively control the flow of high pressure well fluid to the desireddownhole tool or tools.

According to one embodiment, the tool actuation system comprises abarrier member, e.g. a pressure membrane/rupture disc or valve, whichblocks flow of pressurized actuating fluid to a downhole tool. A plungeris movably mounted within a housing and is oriented to transition thebarrier member. For example, the plunger may be positioned to open avalve or to impact a rupture disc in a manner which fractures or weakensthe rupture disc. The plunger is driven by expansion of a suitablematerial within an expansion chamber, and the suitable expansionmaterial may comprise a gas generating energetic material. However, theplunger and the expansion material are uniquely designed so the systemfalls within the US Department of Transportation (DOT) “Not Regulated”class. The design enables shipping of the product without labeling theproduct as explosive and without subjecting the product to the shippingrestrictions required with respect to explosive devices.

Expansion of the selected material within the expansion chamber isinitiated by an initiator device which may be designed to receivesignals from an uphole location, e.g. a surface location. A variety oftechniques and types of systems may be employed to communicate signalsdownhole to the initiator device to selectively initiate opening of theport and flow of pressurized actuating fluid to the downhole tool ortools. By way of example, the signals may be transmitted viacable-to-surface systems, electromagnetic telemetry systems, acoustictelemetry systems, wireline systems, coiled tubing with wirelinesystems, coiled tubing with fiber optic systems, drilling andmeasurement systems (e.g. mud pulse or electromagnetic telemetrysystems), or other suitable telemetry systems. Additionally, the toolactuation system may comprise a plurality of trigger systems, e.g. aplurality of plungers, which cooperate with corresponding barriermembers to enable repeated closing and opening of the port for repeateddownhole tool actuations.

Referring in general to FIGS. 1 and 2, a well system 20 is illustratedas employing an embodiment of a downhole tool actuation system 22 whichis able to selectively actuate a downhole tool 24. By way of example,downhole tool 24 may comprise a packer, a flow valve, or a variety ofother downhole tools that are actuated by pressurized fluid. In manyapplications, the downhole tool or tools 24 may be hydraulicallyactuated by well fluid or by another hydraulic fluid delivered downholealong an appropriate conduit or other flow passage.

In the example illustrated, well system 20 comprises a downholeequipment assembly 26 which incorporates downhole tool 24. The downholeequipment assembly 26 may comprise a bottom hole assembly, a wellcompletion assembly, or other types of downhole equipment selectedaccording to the specific well operation being conducted. The downholeequipment assembly 26 may be delivered downhole along a wellbore 28 froma surface location 30 via a suitable conveyance 32. Depending on thewell application, conveyance 32 may comprise production tubing, coiledtubing, cable, wireline, slick line, or other suitable conveyances.

The downhole tool actuation system 22 comprises a downhole portion 34which may be referred to as the trigger system. The downhole portion 34is selectively operated to control flow of actuating fluid to downholetool 24 based on signals received from a control system 36. In someembodiments, downhole portion 34 operates to open a port 38 which allowshigh pressure well fluid to flow into downhole tool 24 from an annulus40 surrounding the downhole tool 24. The high pressure well fluid servesto actuate downhole tool 24 by shifting the downhole tool to a desiredoperational configuration. However, port 38 may be positioned to controlflow through hydraulic control lines, through an interior of conveyance32, or through other suitable features to selectively enable flow ofactuating fluid to downhole tool 24.

In the example illustrated, control system 36 is positioned at a surfacelocation 30, however the control system also may be positioned at remotelocations or at both remote and well site locations. In someapplications, the control system 36 may be manually operated while inother applications the control system 36 is partially or fully automatedto act upon the occurrence of specific parameters detected downhole orat other locations. If the control system 36 is automated, the controlmay be conducted from a downhole location in certain applications. Inthe example illustrated, however, control system 36 is coupled todownhole portion 34 by a suitable communication line 42 which may be ahard wired or wireless communication line. Depending on the wellapplication, a variety of telemetry systems may be employed forconveying signals between control system 36 and downhole portion 34. Byway of example, signals/commands may be transmitted via acoustictelemetry (e.g. mud pulse telemetry), electromagnetic telemetry, seismictelemetry (e.g. air guns, detonation sources, or impact sourcespositioned at the surface), radio frequency telemetry (e.g. RF tagtelemetry systems), electrically conductive path systems from surface orsubsurface (e.g. wireline or control line type systems), or combinationsof the telemetry systems.

Depending on the specific well application and on the type of telemetrysystem employed to convey signals downhole, the downhole portion 34 mayhave various configurations. As illustrated in greater detail in FIG. 2,for example, the downhole portion 34 may comprise a barrier member 44which initially blocks flow of actuating fluid through port 38. By wayof example, the barrier member 44 comprises a valve or a pressuremembrane, e.g. a rupture disc. In the embodiment illustrated, a plungermember 46 is positioned and oriented to engage barrier member 44.Plunger member 46 is movably, e.g. slidably, mounted within asurrounding housing 48, such as a cylindrical housing. Movement ofplunger member 46 with respect to barrier member 44 serves toselectively transition the barrier member 44 to a flow position whichallows flow of actuating fluid through port 38 to actuate downhole tool24. For example, plunger member 46 may be moved to transition a valve orto fracture a rupture disc so that actuating fluid may freely flowthrough port 38.

Plunger member 46 is moved by an expansion device 50 which may be in theform of a gas generating device. In the example illustrated, expansiondevice 50 is a gas generating device having an expansion chamber 52 inwhich gases are rapidly expanded to drive the plunger member 46 which,in turn, opens port 38. The expansion device 50 comprises an expansionmaterial 54 disposed in expansion chamber 52, and the expansion material54 may be in the form of a gas generating energetic material, e.g. apyrotechnic material. The expansion material 54 rapidly expands uponinitiation of the desired reaction by an initiator device 56 whichreceives command signals from control system 36 via communication line42. As described above, the communication line 42 may be wired orwireless and it may carry a variety of signals depending on the type oftelemetry system employed in the downhole tool actuation system 22.

However, the expansion device 50 is designed as a DOT “Not Regulated”class device to facilitate handling and transport of the device.Specifically, expansion device 50 is designed (and the expansionmaterial 54 and/or plunger member 46 are selected) such that theexpansion device 50 and overall tool system meet the testing criteriarequired for such devices. In this example, the testing criteria includeassessing the expansion material 54 and/or the component containing theexpansion material 54, e.g. expansion chamber 52, to ensure thecomponent/materials are not ruptured or fragmented. The criteria furthercomprise ensuring the surface temperature in the vicinity of theexpansion device 50 containing the expansion material 54 does not exceed100° C. and ensuring the device provides little or no smoke generation.Additionally, the criteria require that the audible report frominitiation of the expansion material does not exceed 150 dB whenmeasured with an ANSI type 1 sound level meter placed not more than 1meter away or does not exceed 140 dB when measured with an ANSI type 2sound level meter placed not more than 1 meter away from the expansionmaterial 54. Furthermore, the criteria require that no mechanicalmovement of more than 1 meter occurs in any direction as result ofinitiation of the expansion material 54, e.g. movement of plunger member46. The structure of plunger member 46 and expansion chamber 52, theamount and type of expansion material 54, and the overall arrangement ofthe expansion device 50 and downhole tool 24, as described andillustrated herein, are designed within these criteria.

Accordingly, use of gas generating energetic material 54 to push theplunger member 46 facilitates the handling, transport, andimplementation of the actuation system 22. By utilizing the gasgenerating energetic material 54 in the manner described, the overallactuation system 22 also avoids generation of fragments and/or releaseof hot gases. The amount of gas generating energetic material 54 and thedesign of plunger member 46 is selected to enable classification of thesystem and components as Not Regulated materials, as described above.This allows the expansion device 50 and other components of theactuation system to be shipped by standard commercial carriers.Consequently, the handling, transport, and implementation of suchdevices are substantially improved and simplified.

Referring generally to FIG. 3, an embodiment of the downhole portion 34of downhole tool actuation system 22 is illustrated as coupled todownhole tool 24. In this embodiment, communication line 42 is awireless communication line and the telemetry system is an acoustic,pressure pulse type telemetry system. Control system 36 controls thedelivery of pressure pulses down hole through wellbore 28 along, forexample, annulus 40. The pressure pulses are received by initiatordevice 56 which comprises a pressure sensor 58 designed to detect aseries of pressure pulses that represent a signature associated withactivation of expansion material 54 within expansion chamber 52.

The pressure sensor 58 works in cooperation with a battery 60 and anelectronics module 62. The battery 60 is configured to supply electricalenergy to electronics module 62 which, in turn, is designed to interpretthe series of pressure pulses detected by pressure sensor 58. If apredetermined series of pressure pulses is detected by electronicsmodule 62, the electronics module outputs an activation signal viaappropriate communication lines 64, e.g. conductors, to initiate theexpansion, e.g. gas generation, of expansion material 54 in expansiondevice 50. By way of example, the communication lines 64 may deliver anappropriate current, spark, chemical, or other signal to initiate therapid expansion within expansion chamber 52. It should be noted thatbattery 60 may be replaced with other electric energy supplies, such ascapacitors or electric supply lines routed downhole. Additionally, theelectronics module 62 may comprise a variety of electronics modules,including processor-based modules. An example of one type of battery andelectronics module which can be employed in the illustrated embodimentis described in U.S. Pat. No. 7,510,001.

Rapid expansion of expansion material 54 drives plunger member 46 alongan interior of housing 48. By way of example, housing 48 may have acylindrical interior 66 which serves as a cylinder along which theplunger member 46 slides to transition barrier member 44. In theembodiment illustrated, barrier member 44 comprises a valve 68 coupledto plunger member 46 by a coupling mechanism 70. As plunger member 46 isforced along interior 66, the coupling mechanism 70 transitions valve 68from a closed position to an open position which allows the flow ofhydraulic actuating fluid through port 38. Valve 68 may comprise avariety of valve types, including sliding sleeve valves and ball valves.As with the previously described embodiments, the expansion device 50,along with expansion material 54/plunger member 46, is designed as a DOTNot Regulated class device to facilitate handling and transport.

Referring generally to FIG. 4, an alternate embodiment of the downholeportion 34 of tool actuation system 22 is illustrated. In thisembodiment, barrier member 44 comprises a pressure membrane 72, e.g. arupture disc, which initially prevents flow of actuating fluid throughport 38. The port 38 may be positioned in a wall of housing 48. Theplunger member 46 comprises an impact member 74 oriented to impactpressure membrane 72 when expansion material 54 expands and forcesplunger member 46 to move along the interior of housing 48. By way ofexample, the impact member 74 may have a pointed end which impacts andfractures the pressure membrane 72 to allow flow of actuating fluidthrough port 38 and along a conduit 76 to downhole tool 24.Alternatively, the impact member 74 and plunger member 46 may bedesigned to sufficiently weaken pressure membrane 72 upon impact toallow the pressure of the actuating fluid to remove the barrier andenable flow to downhole tool 24.

In the example illustrated in FIG. 4, expansion material 54 may again bea gas generating energetic material located within expansion chamber 52.The initiator device 56 is located adjacent expansion device 50 and isdesigned to selectively initiate the expansion of expansion material 54upon receipt of an activating command signal through communication line42. The expansion of material 54 then drives plunger member 46 along theinterior of housing 48 until impact member 74 impacts the pressuremembrane 38 and opens a flow pathway to allow flow of pressurized fluidthrough port 38 to the downhole tool 24. In this latter embodiment, theexpansion device 50 is again constructed as a DOT Not Regulated classdevice.

The specific configuration of the downhole tool actuation system 22 andits downhole portion 34 may be adjusted according to the parameters of agiven well application and/or environment. The type of expansionmaterial 54 may be selected according to the temperatures, pressures,environmental conditions, and/or system conditions related to the welloperation being conducted. Also, the configuration of the plungermember, initiator device, electronics module, housing, barrier member,control system, communication/telemetry system, all may be adjusted orinterchanged according to the needs of a given application.

Additionally, other mechanisms may be combined with, used in cooperationwith, or employed as an alternative to the mechanisms described abovefor selectively transitioning the barrier member 44 to an open flowcondition. In some embodiments, the barrier member may initially beweakened or combined with a weakening material, e.g. a chemical,designed to degrade the barrier member. For example, the pressuremembrane may be selectively exposed to corrosive or reactive materialswhich deconstruct the membrane. Thus, the plunger member 46 may be usedin cooperation with a variety of chemicals or other features designed toweaken or otherwise alter the pressure membrane or other type of barriermember 44 to facilitate opening of the flow port.

Although only a few embodiments of the present invention have beendescribed in detail above, those of ordinary skill in the art willreadily appreciate that many modifications are possible withoutmaterially departing from the teachings of this invention. Accordingly,such modifications are intended to be included within the scope of thisinvention as defined in the claims.

1. A system for use in a well, comprising: a downhole tool to beactuated by pressure exerted by well fluid; and a downhole toolactuation system, comprising: an inlet port in communication with thewell fluid; a pressure sensor for receiving one or more pressure pulses;an electronics module in communication with the pressure sensor, whereinthe electronics module processes the one or more pressure pulses todetect a command for actuating the downhole tool; an expansion devicehaving an expansion chamber for expansion of a gas generating energeticmaterial, wherein the audible report from initiation of the expansiondevice does not exceed 150 dB as measured on an ANSI type I sound levelmeter placed not more than 1 meter away; a plunger disposed in a housingand in communication with the expansion device, wherein the plunger isconstrained to movement of not more than 1 meter in any direction; and abarrier positioned to block flow through the inlet port such thatactuation of the expansion device drives the plunger into the barrier toenable flow through the inlet port.
 2. The system as recited in claim 1,wherein the plunger is figured to rupture the barrier.
 3. The system asrecited in claim 1, wherein the barrier comprises a rupture disc.
 4. Thesystem as recited in claim 1, wherein the plunger is configured toweaken the barrier.
 5. The system as recited in claim 1, wherein theexpansion device locates the gas generating energetic material in thehousing.
 6. The system as recited in claim 1, wherein the downhole toolcomprises a flow valve.
 7. The system as recited in claim 1, wherein thehousing comprises the inlet port to enable exposure of the downholeactuation tool to actuating pressure of the well fluid after the plungerengages the barrier.
 8. A method for actuating a tool downhole,comprising: positioning the tool in a well string, the tool beinghydraulically actuatable by a hydraulic fluid; locating a barrier memberto block flow of the hydraulic fluid through a port to the tool;orienting a plunger between the barrier member and an expansion devicecontaining a gas generating energetic material in a manner such that anyaudible report from initiation of the gas generating energetic materialis less than 140 dB as measured by an ANSI type 2 sound level meterpositioned at a distance of less than 1 meter and such that initiationof the gas generating energetic material provides no mechanical movementof more than 1 meter; and coupling the expansion device to an initiatordevice able to receive signals from uphole regarding actuation of thegas generating energetic material.
 9. The method as recited in claim 8,further comprising sending a signal downhole to the initiator device toactuate the expansion device and drive the plunger into the barriermember.
 10. The method as recited in claim 8, further comprisinglocating a rupture disc in the port.
 11. The method as recited in claim8, wherein orienting comprises slidably orienting the plunger in acylindrical housing adjacent the barrier.
 12. The method as recited inclaim 9, wherein sending the signal downhole comprises sending anacoustic signal downhole to the initiator device.
 13. The method asrecited in claim 9, wherein sending the signal downhole comprisessending an electromagnetic signal downhole to the initiator device. 14.The method as recited in claim 9, wherein sending the signal downholecomprises sending a seismic telemetry signal downhole to the initiatordevice.
 15. The method as recited in claim 9, wherein sending the signaldownhole comprises sending a radiofrequency signal downhole to theinitiator device.
 16. The method as recited in claim 8, furthercomprising forming the expansion device with the gas generatingenergetic material located in an internal expansion chamber.
 17. Themethod as recited in claim 8, further comprising hydraulically actuatingthe tool with well fluid.
 18. A method of constructing and actuatabledownhole tool system, comprising: providing a port in communication witha downhole tool which may be hydraulically actuated; positioning abarrier member to selectively block flow of fluid through the port;orienting a plunger member to selectively transition the barrier memberin a manner which allows flow of actuating fluid through the port toactuate the downhole tool; locating an expansion chamber adjacent theplunger member; placing an expansion material in the expansion chamber,the expansion material being selectively expandable to drive the plungermember to transition the barrier member; and simplifyingtransportability of the actuatable downhole tool system by: ensuring theexpansion chamber is not ruptured; maintaining temperature in the areasurrounding the expansion material to a temperature that does not exceed100° C.; minimizing the audible report from initiation of the expansionmaterial to less than 150 dB as measured by an ANSI type 1 sound levelmeter at not more than 1 meter away; and limiting mechanical movementdue to initiation of the expansion material to less than 1 meter. 19.The method as recited in claim 18, wherein positioning the barriermember comprises positioning a valve.
 20. The method as recited in claim18, wherein positioning the barrier member comprises positioning arupture disc.